diff --git a/library/psa_crypto_rsa.c b/library/psa_crypto_rsa.c
index 08db7a4..271b0d5 100644
--- a/library/psa_crypto_rsa.c
+++ b/library/psa_crypto_rsa.c
@@ -360,27 +360,19 @@
         return( PSA_ERROR_INVALID_ARGUMENT );
 #endif
 
-#if defined(BUILTIN_ALG_RSA_PKCS1V15_SIGN)
-    /* For PKCS#1 v1.5 signature, if using a hash, the hash length
-     * must be correct. */
-    if( PSA_ALG_IS_RSA_PKCS1V15_SIGN( alg ) &&
-        alg != PSA_ALG_RSA_PKCS1V15_SIGN_RAW )
+    /* For signatures using a hash, the hash length must be correct. */
+    if( alg != PSA_ALG_RSA_PKCS1V15_SIGN_RAW )
     {
         if( md_info == NULL )
             return( PSA_ERROR_NOT_SUPPORTED );
         if( mbedtls_md_get_size( md_info ) != hash_length )
             return( PSA_ERROR_INVALID_ARGUMENT );
     }
-#endif /* BUILTIN_ALG_RSA_PKCS1V15_SIGN */
-
-#if defined(BUILTIN_ALG_RSA_PSS)
-    /* PSS requires a hash internally. */
-    if( PSA_ALG_IS_RSA_PSS( alg ) )
+    else
     {
-        if( md_info == NULL )
-            return( PSA_ERROR_NOT_SUPPORTED );
+        if( hash_alg != 0 )
+            return( PSA_ERROR_INVALID_ARGUMENT );
     }
-#endif /* BUILTIN_ALG_RSA_PSS */
 
     return( PSA_SUCCESS );
 }
@@ -512,7 +504,7 @@
                                              mbedtls_psa_get_random,
                                              MBEDTLS_PSA_RANDOM_STATE,
                                              MBEDTLS_RSA_PUBLIC,
-                                             MBEDTLS_MD_NONE,
+                                             md_alg,
                                              (unsigned int) hash_length,
                                              hash,
                                              signature );